Adds appveyor config

Author: sdispater

appveyor.yml

@@ -0,0 +1,29 @@
+build: false
+
+environment:
+  matrix:
+    - PYTHON: "C:/Python27"
+    - PYTHON: "C:/Python27-x64"
+    - PYTHON: "C:/Python33"
+    - PYTHON: "C:/Python33-x64"
+    - PYTHON: "C:/Python34"
+    - PYTHON: "C:/Python34-x64"
+    - PYTHON: "C:/Python35"
+    - PYTHON: "C:/Python35-x64"
+
+install:
+  - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
+
+  # Upgrade to the latest version of pip to avoid it displaying warnings
+  # about it being out of date.
+  - "pip install --disable-pip-version-check --user --upgrade pip"
+
+  # Install dependencies
+  - "%CMD_IN_ENV% pip install -r tests-requirements.txt"
+  - "%CMD_IN_ENV% pip install codecov"
+
+test_script:
+  - "py.test --cov=pendulum --cov-config=.coveragerc tests/"
+
+after_test:
+  - "codecov"